I don't know how to do #9. Please help!
(a)
Arc AC = 88 degrees (half of angle B)
Arc AB = 110 degrees
Arc BC = 360 - 88 - 110 = 162
b = 1\2 arc BC = 1/2 (162) = 81 degrees
(b)
The square of the tangent is equal to the external part of the secent times the whole secant.
$\displaystyle 5^2=4(x+4)$
$\displaystyle 25=4x+16$
Finish up.
(3)
Use the Pythagorean theorem to find the length of the other chord segment which is 4. (It's a 3-4-5 right triangle.)
If two chords intersect in a circle, then the products of the measures of the segments of the chords are equal.
$\displaystyle 4x=(3)(6)$
Finish up.